摘要
新型的模块化变换装置在高压大功率场合逐渐得到应用,概述了模块化多电平换流器(modular multilevel converter,MMC),通过分析MMC的拓扑结构及其工作机制,建立了基于开关函数的MMC数学模型,在此基础上采用载波正负反相层叠脉冲宽度调制技术(POD-PWM)及基于排序法的电容电压平衡控制,实时检测换流器各子模块电容电压并进行排序,根据每一相上、下桥臂电流方向,对子模块进行充电、放电或者旁路操作,达到控制电容电压平衡的目的。在Matlab-Simulink环境下搭建仿真模型,仿真结果表明该方法可行且有效,实现了换流器正常运行、电容电压稳定的预期目标。
The new type of modular conversion device has been gradually applied in high voltage and power situation.The fundamental concept of the modular multilevel converter(MMC) was described. Through the analysis of the topological structure and working mechanism of MMC, the MMC mathematical model based on switch function was built. On the basis, through carrier phase opposition disposition pulse width modulation(POD-PWM) and capacitor voltage balancing control based on sequencing method, the capacitor voltage of each submodular of the convertor was detected in real time and sequenced. Based on upper and lower bridge current direction of each phase, the operation of charging and discharging or bypass operation to submodulars was carried on to control the capacitor voltage balance. The simulation model was built under Matlab-Simulink circumstance. The simulation results show that the control strategy is practical and valid, realizing the expected goal of regular operation of the converter and the stability of capacitor voltage.
出处
《电源技术》
CAS
CSCD
北大核心
2014年第5期943-946,共4页
Chinese Journal of Power Sources
基金
国家自然科学基金(61340015
51077125)
关键词
模块化多电平换流器
开关函数
电压均衡控制
modular multilevel converter
switch function
voltage balancing control